Joba Chamberlain has a much different look in Detroit.Credit: Getty Images

Joba Chamberlain burst on the scene seven years ago this week as a flame-throwing reliever the Yankees anticipated would be a stalwart on their pitching staff for years.

If the Yankees had projected things correctly, Chamberlain wouldn’t have been giving a 10-minute press conference Monday for a visiting player.

The 27-year-old, who made the “Joba Rules” part of daily language and whose role was a constant source of debate returned to New York last night, this time as a member of the Tigers, who are in first place in the AL Central with him as their primary eighth-inning reliever.

Chamberlain took a 3.02 ERA over 49 appearances into Monday. He is on a one-year, $2.5 million deal with Detroit and came into spring training not necessarily anointed the eighth-inning man to Joe Nathan.

“I think the biggest adjustment was continuing in spring training to go out and earn my job,” Chamberlain said. “I knew they obviously brought me over for a reason and they have good arms but going out, and after the terrible year that I had last year, I had to continue to prove and show what I could do. Just to earn that spot back and obviously they signed Joe and my job is to get that ball to him, that’s what I felt like from day one but obviously that’s played itself out well.”

Chamberlain’s return came after a quiet end to one of the more-hyped major league debuts in recent memory. He ended a Yankee career of 260 appearances on Sept. 27 at Houston. He was used as a mop-up reliever by the end of the season due to a 4.93 ERA.

It wasn’t supposed to be that way for Chamberlain and the Yankees in a phenomenon that preceded "Linsanity" by five years when he made his first start against Toronto on June 3, 2008.

It was supposed to be a continuation of the August 2007 hype that spawned the “Joba Rules” T-shirts. Instead, seven years turned into a lifetime of ups — a 2009 World Series title — and downs — including a DUI charge in October 2008, a midge attack in the playoffs at Cleveland in 2007, Tommy John surgery in 2011 and an injured ankle from jumping on a trampoline in 2012 that spawned criticism of him as a father..

“If you think that [what could have been] life would be pretty boring,” Chamberlain said. “I’ve experienced so much. The game of baseball is so short and the game of life so much bigger. This game has taught me so much. It taught me to be patient with the rules and five days rest and eight days rest when you started. I wouldn’t change anything. It taught me to be a better man, a better person, a better father and in the end it taught me to be a better teammate.

“It wasn’t always easy, I’d be lying if I didn’t say I got frustrated at times but at the end it made me a better person. It made me a better baseball player and I use all of things my first seven years in this offseason to figure out how I can make myself better and without those experiences, without those opportunities, I don’t think I’d be having the year I’m having this year.”

Besides having a 2.40 ERA over his last 33 outings since May 14 and leading the American League with 22 holds, Chamberlain has mixed in a curveball. He is throwing it 21 percent of the time while throwing 43 percent fastballs.

That’s not the only difference. After spending his first eight years in pro baseball trying to adhere to the Yankees’ no facial hair policy, Chamberlain has let the beard continue to grow after starting it in spring training.

“I guess when you’re told to shave every day for so long, you just say forget it after a while,” he said. “It’s not as easy as I thought but once it gets long you have to use special conditioners and stuff like that. After a while, it’s a lot, you got to comb it and make sure nothing’s stuck in it or birds coming out of it. It’s one of those things that I don’t even notice anymore. You’re told to shave and I’m extremely lazy and I don’t like to shave, so I just said forget it. I was just going to do it for spring training and then I didn’t shave one day and seven months later I still haven’t shaved.”